Overwatered plants often show yellowing leaves, a mushy or foul-smelling base, and consistently soggy soil, while underwatered plants show dry, crispy leaf edges, wilting that recovers after watering, and soil that pulls away from the pot’s sides. Checking soil moisture an inch or two down with your finger before every watering is the single best habit for avoiding both.

Early morning is generally best, since it gives plants moisture before the day’s heat while allowing foliage to dry off, which helps prevent fungal disease. Evening watering works in a pinch but can leave leaves damp overnight in humid climates, so morning is the safer default where possible.

Yes — rain that actually reaches the soil or pot surface adds real moisture and should be subtracted from your weekly target, which is exactly what this calculator does. Rain blocked by roof overhangs, dense canopy, or umbrellas over containers generally doesn’t count, since it never reaches the root zone.

Unglazed terracotta and clay pots are porous and wick moisture out through their walls, so they dry out noticeably faster than plastic, glazed ceramic, or metal containers. If you’re using terracotta, it’s reasonable to water somewhat more often than this calculator’s baseline suggests.

Plants grow faster and lose more water through their leaves in the warm, bright days of summer, while growth slows dramatically in winter’s shorter, cooler days — often to the point where overwatering becomes the bigger risk. Use the Seasonal Adjustment Guide above to see how much your specific plant’s needs shift across the year.